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Abstract:

A two-piece slot motor housing assembly is provided. The slot motor
housing assembly includes a first J-shaped body baying a lower, first end
and a second, J-shaped body having a lower, first end. The first and
second J-shaped bodies coupled to form a U-shaped assembly. The first
J-shaped body first end overlaps the second J-shaped body first end.

Claims:

1. (canceled)

2. The slot motor housing assembly of claim 3 wherein: said first
J-shaped body first end overlaps said second J-shaped body first end in a
longitudinal direction.

3. A slot motor housing assembly for a circuit breaker slot motor
assembly, said slot member assembly including a number of magnetically
permeable members, each magnetically permeable member including a
U-shaped body, said slot motor housing assembly comprising: a first
J-shaped body having a lower, first end; a second J-shaped body having a
lower, first end; said first J-shaped body includes an inner sidewall, a
first depending sidewall, and a second depending sidewall, said first
J-shaped body first depending sidewall and said first J-shaped body
second depending sidewall extending generally perpendicular to said first
J-shaped body inner sidewall; said second J-shaped body includes an inner
sidewall, a first depending sidewall, and a second depending sidewall,
said second J-shaped body first depending sidewall and said second
J-shaped body second depending sidewall extending generally perpendicular
to said second J-shaped body inner sidewall; said first J-shaped body
first depending sidewall at said first J-shaped body first end overlaps
said second J-shaped body first depending sidewall at said second
J-shaped body first end in an axial direction; said first J-shaped body
second depending sidewall at said first J-shaped body first end overlaps
said second J-shaped body second depending sidewall at said second
J-shaped body first end in an axial direction; said first and second
J-shaped bodies coupled to form a U-shaped assembly; and wherein said
U-shaped assembly forms a continuous U-shaped cavity.

4. The slot motor housing assembly of claim 3 wherein said first J-shaped
body first end includes a number of inwardly extending ledges.

5. The slot motor housing assembly of claim 3 wherein: said first
J-shaped body includes an upper, second end; said second J-shaped body
includes an upper, second end; and said first J-shaped body second end
and said second J-shaped body second end each include a tab extending
generally in an axial-longitudinal plane.

8. The stationary contact assembly of claim 9 wherein: said first
J-shaped body first end overlaps said second J-shaped body first end in
an axial direction; and said first J-shaped body first end overlaps said
second J-shaped body first end in a longitudinal direction.

9. A stationary contact assembly comprising: a stationary conductor
including an elongated body with a first end and a medial portion, said
stationary conductor body first end curled over said stationary conductor
body medial portion; an arc chute assembly including a first lateral side
planar member, a second lateral side planar member and a number of
conductive plates, said conductive plates disposed in a spaced relation
to each other and disposed between said arc chute first lateral side
planar member and said arc chute second lateral side planar member; said
arc chute assembly disposed over said stationary conductor body medial
portion adjacent said stationary conductor body first end; a U-shaped
slot motor assembly including a number of U-shaped magnetically permeable
members and a housing assembly; said slot motor magnetically permeable
members each including a U-shaped body; said slot motor housing assembly
including a first J-shaped body having a lower, first end and a second,
J-shaped body having a lower, first end; said first J-shaped body
includes an inner sidewall, a first depending sidewall, and a second
depending sidewall, said first J-shaped body first depending sidewall and
said first J-shaped body second depending sidewall extending generally
perpendicular to said first J-shaped body inner sidewall; said second
J-shaped body includes an inner sidewall, a first depending sidewall, and
a second depending sidewall, said second J-shaped body first depending
sidewall and said second J-shaped body second depending sidewall
extending generally perpendicular to said second J-shaped body inner
sidewall; said first J-shaped body first depending sidewall at said first
J-shaped body first end overlaps said second J-shaped body first
depending sidewall at said second J-shaped body first end in an axial
direction; said first J-shaped body second depending sidewall at said
first J-shaped body first end overlaps said second J-shaped body second
depending sidewall at said second J-shaped body first end in an axial
direction; said first and second J-shaped bodies slot motor housing
assembly coupled to form a U-shaped assembly; wherein said U-shaped
assembly forms a continuous U-shaped cavity, said U-shaped cavity
generally corresponding to said U-shaped magnetically permeable members;
said slot motor magnetically permeable members disposed in said U-shaped
assembly; and the bight of said U-shaped slot motor assembly disposed
under said conductor body first end.

10. The stationary contact assembly of claim 9 wherein said first
J-shaped body first end includes a number of inwardly extending ledges.

11. The stationary contact assembly of claim 9 wherein: said first
J-shaped body includes an upper, second end; said second J-shaped body
includes an upper, second end; said first J-shaped body second end and
said second J-shaped body second end each include a tab extending
generally in an axial-longitudinal plane; said arc chute first lateral
side planar member disposed inside said first J-shaped body second end
tab; and said arc chute second lateral side planar member disposed inside
said second J-shaped body second end tab.

12. The stationary contact assembly of claim 7 wherein said U-shaped
assembly is generally symmetrical about a longitudinal-lateral plane.

13. (canceled)

14. The circuit breaker assembly of claim 15 wherein: said first J-shaped
body first end overlaps said second J-shaped body first end in an axial
direction; and said first J-shape body first end overlaps said second
J-shaped body first end in a longitudinal direction.

15. A circuit breaker assembly comprising: a housing assembly defining a
number of contact chambers; a number of conductor assemblies each having
a pair of separable contacts; each conductor assembly further including a
stationary contact assembly, each stationary contact assembly including a
stationary conductor, an arc chute assembly, and a U-shaped slot motor
assembly; each said stationary conductor including an elongated body with
a first end and a medial portion, said stationary conductor body first
end curled over said stationary conductor body medial portion; each said
arc chute assembly including a first lateral side planar member, a second
lateral side planar member and a number of conductive plates, said
conductive plates disposed in a spaced relation to each other and
disposed between said arc chute first lateral side planar member and said
are chute second lateral side planar member; each said are chute assembly
disposed over said stationary conductor body medial portion adjacent said
stationary conductor body first end; each said U-shaped slot motor
including a number of U-shaped magnetically permeable members and a
housing assembly; each said motor magnetically permeable members each
including a U-shaped body; each said slot motor housing assembly
including a first J-shaped body having a lower, first end and a second,
J-shaped body having a lower, first end; said first J-shaped body
includes an inner sidewall, a first depending sidewall, and a second
depending sidewall, said first J-shaped body first depending sidewall and
said first J-shaped body second depending sidewall extending generally
perpendicular to said first J-shaped body inner side-wall; said second
J-shaped body includes an inner sidewall, a first depending sidewall, and
a second depending sidewall, said second J-shaped body first depending
sidewall and said second J-shaped body second depending sidewall
extending generally perpendicular to said second J-shaped body inner
sidewall; said first J-shaped body first depending sidewall at said first
J-shaped body first end overlaps said second J-shaped body first
depending sidewall at said second J-shaped body first end in an axial
direction; said first J-shaped body second depending sidewall at said
first J-shaped body first end overlaps said second J-shaped body second
depending sidewall at said second J-shaped body first end in an axial
direction; said first and second J-shaped bodies slot motor housing
assembly coupled to form a U-shaped assembly; wherein said U-shaped
assembly forms a continuous U-shaped cavity, said U-shaped cavity
generally corresponding to said U-shaped magnetically permeable members;
said slot motor magnetically permeable members disposed in said U-shaped
assembly; and the bight of said U-shaped slot motor disposed under said
conductor body first end.

16. The circuit breaker assembly of claim 15 wherein said first J-shaped
body first end includes a number of inwardly extending ledges.

17. The circuit breaker assembly of claim 15 wherein: said first J-shaped
body includes an upper, second end; said second J-shaped body includes an
upper, second end; said first J-shaped body second end and said second
J-shaped body second end each include a tab extending generally in an
axial-longitudinal plane; said arc chute first lateral side planar member
disposed inside said first J-shaped body second end tab; and said arc
chute second lateral side planar member disposed inside said second
J-shaped body second end tab.

18. The circuit breaker assembly of claim 15 wherein said U-shaped
assembly is generally symmetrical about a longitudinal-lateral plane.

Description:

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The disclosed and claimed concept relates to circuit breakers and,
more specifically, to a slot motor for a circuit breaker wherein the slot
motor includes a multi-piece cover assembly.

[0003] 2. Background Information

[0004] Circuit breakers, including molded case circuit breakers, have at
least one pair of separable contacts. A first contact is fixed within the
molded case housing and the other contact, the "movable contact," is
coupled to an operating mechanism. Both contacts are disposed on "arms"
that are in electrical communication with either the line or load coupled
to the circuit breaker. The operating mechanism is structured to more the
movable contact between a first, open position wherein the movable
contact is spaced from the fixed contact, and a second, closed position
wherein the fixed and movable contacts are in contact and electrical
communication. The operating mechanism may be operated manually or by the
circuit breaker's trip mechanism. To enhance the speed of separation of
the contacts, the contacts may be disposed within a slot motor.

[0005] A slot motor is a ring, i.e. loop-shaped device, or partial ring,
made of magnetically permeable material which is disposed about, or
partially about, the contacts and contact arms of a circuit breaker. When
the circuit is live, an electrical arc may be drawn between the
electrical contacts during separation. The electrical current interacts
electromagnetically with the slot motor to induce a magnetic field in the
magnetic material of the slot motor which in turns interacts with the
separating contact arms to accelerate the contact opening process.

[0006] In one embodiment, slot motors generally have two assemblies, an
upper assembly and a lower assembly. Both upper and lower assemblies
include a housing assembly and a plurality of plates, or laminations,
composed of the magnetically permeable material. The lower assembly is
disposed below the fixed contact. As shown in FIG. 1, the upper assembly
is an inverted U-shaped assembly having a housing assembly 1 and a
plurality of plates 2. The "U-shape" includes a bight portion 3, i.e. a
cross-portion, and two legs 4, 5. As used herein, "U-shaped" is
interpreted broadly and includes an assembly having corners forming
generally right angles, i.e. a squared U-shape. The upper slot motor is
structured to be disposed over the movable contact wherein the tips of
the upper assembly leg contact the lower assembly. The legs of the
U-shaped upper assembly have an extended length to accommodate the path
of travel of the movable contact arm. That is, the movable contact is
disposed between the legs of the upper assembly and as the movable
contact moves between the first, open position and the second, closed
position, the movable contact moves from a position adjacent to the upper
assembly bight to a position adjacent the tips of the legs. Accordingly,
the legs must have a sufficient length to accommodate the path of travel
of the movable contact arm. It should further be noted that the movable
contact arm may, due to manufacturing tolerances, be free to shift a
short distance laterally while moving. This design, i.e. a full loop,
requires a significant amount of space in the circuit breaker housing
assembly. Further, the circuit breaker housing assembly must have a
height sufficient to accommodate the loop shaped slot motor.

[0007] In a full loop embodiment, the upper slot motor, i.e. the inverted
U-shaped assembly included a U-shaped housing assembly. The upper slot
motor housing assembly included an inner U-shaped member with forward and
aft outwardly extending, depending sidewalls. Further, the tips of the
tines included an outwardly extending depending sidewall that extended
between the forward and aft sidewalls. Thus, the U-shaped magnetically
permeable members could be moved longitudinally (in a direction parallel
to the axis of the tines) into the upper slot motor housing assembly.

[0008] A disadvantage of such a U-shaped housing assembly was that, in
view of the desired thinness of the U-shaped housing assembly walls,
there were difficulties in molding the U-shaped housing assembly. For
example, the tines of the U-shaped housing assembly tended to collapse
toward each other. One solution to this problem was to create a two-piece
housing, assembly having mirror image elements. These elements were
coupled to each other with abutting surfaces. That is, the ends of the
separate elements abutted each other at the interface. In such
embodiments, the ends of the separate elements minimally overlapped, but,
as used herein, surfaces with such a minimal amount of overlap shall be
identified as "abutting surfaces." Such abutting surfaces could be
subject to electrical arcing therebetween, i.e. the arc could penetrate
the interface. It is further noted that the distal ends of the upper slot
motor were maintained in a spaced relationship by the stationary contact.

[0009] In another embodiment, the slot motor is a partial loop. That is,
the slot motor extends under the fixed contact and upwardly on either
side of the path of travel of the movable contact. Thus, the partial loop
does not include an upper cross member and is shaped like an upright "U."
A slot motor that is a partial loop is, essentially, as effective as a
full loop slot motor in that the accelerating forces are primarily
generated near the point that the arc is generated, i.e. near the
stationary contact. Thus, as a partial loop slot motor, i.e. a slot motor
having an upright U-shape, does not have an upper cross-member, a partial
loop slot motor can fit within a smaller circuit breaker housing assembly
and takes up less space within such a circuit breaker housing assembly.

[0010] The housing assembly for a partial loop slot motor included a
forward U-shaped wall with an axially depending sidewall. In this
configuration, the housing assembly defined a pocket into which U-shaped
magnetically permeable members could be placed. That is, the U-shaped
magnetically permeable members were moved axially into the partial loop
slot motor housing assembly. In this configuration, the partial loop slot
motor housing assembly did not cover the of side of the magnetically
permeable members, i.e. the side opposite the housing assembly forward
wall. Tape, or a similar material, was used to protect the of side of the
magnetically permeable members, it is noted that a two-piece upright
U-shape housing assembly, wherein the tips of the U-shape housing
assembly were not separated by the stationary contact would be subject to
collapse. That is, one problem with a two-piece upright U-shape housing
assembly would be that the pieces could pivot relative to each other.

[0011] There is, therefore, a need for a slot motor housing assembly for a
partial loop slot motor, i.e. a slot motor having an upright U-shape,
wherein the slot motor housing assembly is easy to manufacture. There is
a further need for a partial loop slot motor housing assembly that
resists arcing between a multiple piece housing assembly. There is a
further need for a partial loop slot motor housing assembly that resists
the collapse of the partial loop slot motor housing assembly. There is a
further need for the improved slot motor to be compatible with existing
circuit breaker housings.

SUMMARY OF THE INVENTION

[0012] These needs, and others, are met by at least one embodiment of the
disclosed concept which provides a two-piece slot motor housing assembly
having an overlapping interface. As noted above, single piece housing
assemblies have molding issues. Thus, the two-piece construction provides
for a housing assembly that is easy to manufacture. The overlapping
interface resists arcing between the multiple piece housing assembly.
Further, each piece of the housing assembly is structured to be coupled
to the arc chute housing. The support provided by the arc chute housing
maintains the slot motor housing assembly elements in a spaced
relationship. That is, the two pieces of the slot motor housing assembly
do not collapse toward each other. It is noted that the stated problems
are solved by the configuration, i.e. shape, of the two-piece slot motor
housing assembly.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] A full understanding of the disclosed and claimed concept can be
gained from the following description of the preferred embodiments when
read in conjunction with the accompanying drawings in which:

[0014] FIG. 1 is an isometric view of the prior art upper slot motor.

[0015] FIG. 2 is a cross-sectional side view of a circuit breaker.

[0016] FIG. 3 is an isometric exploded upward view of a circuit breaker.

[0017] FIG. 4 is an isometric downward view of a circuit breaker.

[0018] FIG. 5 is a detail isometric view of a stationary contact assembly.

[0022] The following directional terms apply to the slot motor assembly:
the "longitudinal direction" extends in the direction of the longitudinal
axis of the slot motor legs or tines, as described below. That is, the
"longitudinal direction" is generally the vertical direction as shown in
the Figures, The "lateral direction" extends in a direction generally
perpendicular to the "longitudinal direction" and generally horizontally
across both the motor legs or tines, as described below. The "axial
direction" is generally perpendicular to both the "longitudinal
direction" and the "lateral direction." That is, the "axial direction"
extends generally horizontally between the slot motor legs or tines, as
described below. Further, with respect to the slot motor assembly, as
used herein the "inner" side is the side adjacent the stationary contact,
as described below, i.e. generally the inner side of the U-shaped
assembly. Conversely, the "outer" side is the side disposed away from the
stationary contact, as described below, i.e. generally the outer side of
the U-shaped assembly.

[0023] As used herein, "coupled" means a link between two or more
elements, whether direct or indirect, so long as a link occurs. An object
resting on another object held in place only by gravity is not "coupled"
to the lower object unless the upper object is otherwise maintained
substantially in place. That is, for example, a book on a table is not
coupled thereto, but a book glued to a table is coupled thereto.

[0024] As used herein, "directly coupled" means that two elements are
directly in contact with each other.

[0025] As used herein, "fixedly coupled" or "fixed" means that two
components are coupled so as to move as one while maintaining a constant
orientation relative to each other. Similarly, two or more elements
disposed in a "fixed relationship" means that two components maintain a
substantially constant orientation relative to each other. As used
herein, the word "unitary" means a component is created as a single piece
or unit. That is, a component that includes pieces that are created
separately and then coupled together as a unit is not a "unitary"
component or body.

[0026] As used herein, "associated" means that the identified components
are related to each other, contact each other, and/or interact with each
other. For example, an automobile has four tires and four hubs, each hub
is "associated" with a specific tire.

[0027] As used herein, "engage," when used in reference to gears or other
components having teeth, means that the teeth of the gears interface with
each other and the rotation of one gear causes the other gear or other
component to rotate/move as well. As used herein, "engage," when used in
reference to components not having teeth means that the components are
biased against each other.

[0028] Directional phrases used herein, such as, for example and without
limitation, top, bottom, left, right, upper, lower, front, back, and
derivatives thereof, relate to the orientation of the elements shown in
the drawings and are not limiting upon the claims unless expressly
recited therein.

[0029] As used herein, "correspond" indicates that two structural
components are similar in size, shape or function. With reference to one
component being inserted into another component or into an opening in the
other component, "corresponding " means components are sized to engage or
contact each other with a minimum amount of friction. Thus, an opening
which corresponds to a member is sized slightly larger than the member so
that the member can pass through the opening with a minimum amount of
friction. This definition is modified if the two components are said to
fit "snugly" together. In that situation, the difference between the size
of the components is even smaller whereby the amount of friction
increases. If one or more components are resilient, a "snugly
corresponding" shape may include one component, e.g. the component
defining the opening being smaller than the component inserted therein.
Further, as used herein, "loosely correspond" means that a slot or
opening is sized to be larger than an element disposed therein. This
means that the increased size of the slot or opening is intentional and
is more than a manufacturing tolerance.

[0030] As used herein, "more than minimally overlap" means that elements
overlap by more than 0.02 inch.

[0031] As used herein, "effectively overlap" means that elements overlap
by more than 0.05 inch.

[0032] As used herein, "efficiently overlap" means that elements overlap
by more than 0.1 inch.

[0033] As used herein, "at" means on or near.

[0034] As shown in FIG. 2, a circuit breaker 10 includes a housing
assembly 12 and a number of conductor assemblies 13 each including a pair
of separable contacts 14. Typically, there is one conductor assembly 13
for each pole of the circuit breaker 10. An exemplary three pole circuit
breaker 10 is shown in FIGS. 3 and 4 (base portion 20 only). The housing
assembly 12 includes an elongated base portion 20 which is coupled to an
elongated primary cover 22. The base portion 20 includes a plurality of
internal walls 24 defining number of elongated cavities 26. In an
exemplary embodiment, there is one cavity 26 for each pole of the circuit
breaker 10. The primary cover 22 also includes a plurality of internal
walls 30 which also define a number of elongated cavities 32. As noted
above, in a three-pole circuit breaker 10 there are three base portion
cavities 26 and three primary cover cavities 32. The base portion
cavities 26 and primary cover cavities 32 extend generally parallel to
each other and parallel to a longitudinal axis of the housing assembly
12. The base portion cavities 26 generally align with the primary cover
cavities 32 so that when the primary cover 22 is coupled to the base
portion 20, the base portion cavities 26 and the primary cover cavities
32 define a number of contact chambers 34 (FIG. 4), and in an exemplary
embodiment with a three-pole circuit breaker 10, three contact chambers
34.

[0035] Each conductor assembly 13, shown in FIG. 2, includes substantially
similar elements and, as such, only one conductor assembly 13 will be
described. Each conductor assembly 13 includes a stationary conductor 40,
a stationary contact 42, a movable conductor 44, and a movable contact
46. It is noted that only a portion of the current path along the movable
conductor is shown. The stationary contact 42 is coupled to, and in
electrical communication with, the stationary conductor 40. In an
exemplary embodiment, the stationary contact 42 is directly coupled to
the stationary conductor 40. The movable contact 46 is coupled to, and in
electrical communication with, the movable conductor 44. In an exemplary
embodiment, the movable contact 46 is directly coupled to the movable
conductor 44. The movable contact 46, and more specifically, the movable
conductor 44, is coupled to an operating mechanism 52. The operating
mechanism 52 is structured to move the movable contact 46 between a
first, open position (not shown) wherein the contacts 14 are separated,
and a second, closed position (shown) wherein the contacts 14 are in
electrical communication. The operating mechanism 52 is coupled to a trip
mechanism 54 (shown schematically) and a handle 56. Thus, the operating
mechanism 52 may be actuated manually by the handle 56, or, actuated in
response to an over-current condition by the trip mechanism 54.

[0036] The stationary conductor 40 and stationary contact 42 are also part
of a stationary contact assembly 60, shown in FIG. 5. The stationary
contact assembly 60 further includes an arc chute assembly 70 and a slot
motor assembly 80. The stationary conductor 40 is, in an exemplary
embodiment, an elongated body 62 including a first end 64, a medial
portion 66, and a second end 68. The stationary conductor body first end
64 is curled over the stationary conductor body medial portion 66 with a
space or gap between the stationary conductor body first end 64 and the
stationary conductor body medial portion 66. That is, the stationary
conductor body medial portion 66 includes a planar portion 65 and an
arcuate portion 67. The arcuate portion 67 extends over an arc of at
least ninety degrees and, as shown, in one embodiment over an arc of
about one hundred and eighty degrees. As shown, in one embodiment the
stationary conductor body first end 64 is a planar member that extends in
a plane generally parallel to the stationary conductor body medial
portion planar portion 65.

[0037] The arc chute 70 includes a first lateral side planar member 72, a
second lateral side planar member 74 and a number of conductive plates
76. The conductive plates 76 are disposed in a spaced relation to each
other and disposed between the arc chute first lateral side planar member
72 and the arc chute second lateral side planar member 74. The arc cute
70 is disposed over the stationary conductor body medial portion 66
adjacent the stationary conductor body first end 64. Arc chute 70 is
structured to absorb and dissipate an arc created by separation of the
contacts 14. Arc chute 70 is sized to correspond to, i.e. fit within, a
contact chamber 34. That is, the spacing between the arc chute first
lateral side planar member 72 and the arc chute second lateral side
planar member 74 generally corresponds to the width of a contact chamber
34. In one embodiment, the width of the arc chute 70 loosely corresponds
to the width of the contact chamber 34. Each arc chute lateral side
planar member 72, 74 further includes an extension 78 that extends toward
the stationary conductor body first end 64. The slot motor assembly 80 is
a U-shaped assembly. As used herein, a "U-shaped" element includes a
bight (or cross member) and two tines (or legs). Further, as used herein,
the tines of a U-shaped body extend generally perpendicular to, and in
the same direction from, the bight. The transition between the bight and
the tines may be curved, as shown in FIG. 5, or at generally right
angles. The slot motor assembly 80 includes a number of magnetically
permeable members 82 and a housing assembly 90. The slot motor assembly
magnetically permeable members 82 each include a U-shaped body 84. The
slot motor assembly magnetically permeable members 82 are disposed in a
stack with each slot motor assembly magnetically permeable member 82
adjacent another slot motor assembly magnetically permeable member 82.

[0038] As shown in FIG. 6, the slot motor assembly housing assembly 90
includes a first J-shaped body 92 and a second, J-shaped body 94. The
first J-shaped body 92 includes a lower first end 100, a medial portion
102 and an upper second end 104. The second, J-shaped body 94 includes a
lower first end 110, a medial portion 112 and an upper second end 114.
The first and second J-shaped bodies 92, 94 are structured to fit
together in an overlapping manner. That is, the first J-shaped body 92,
shown in FIG. 7, further includes an inner sidewall 106, a first
depending sidewall 107 and a second depending sidewall 108 (FIG. 6). The
first J-shaped body inner sidewall 106 is generally L-shaped and consists
of two generally planar members 109. The first J-shaped body depending
sidewalls 107, 108 are generally planar. The first J-shaped body
depending sidewalls 107, 108 extend generally perpendicular to the first
J-shaped body inner sidewall planar members 109. It is noted that the
outer edge of the first J-shaped body depending sidewalls 107, 108
adjacent the vertex of the first "J"-shaped body inner sidewall 106 are
curved thereby giving the first J-shaped body 92 its "J" shape. An end
sidewall 103 extends between the first J-shaped body depending sidewalls
107, 108 at the first J-shaped body upper second end 104. As shown, the
first J-shaped body end sidewall 103 may include a medial extension 105.
In this configuration, the first J-shaped body 92 defines a cavity 101 on
the outer side of the first J-shaped body 92. The first J-shaped body
cavity 101 is sized to correspond to about half of the stack of
magnetically permeable members 82. That is, the right half of the stack
of magnetically permeable members 82 fits within the first J-shaped body
cavity 101.

[0039] Similarly, the second J-shaped body 94, shown in FIG. 8 further
includes an inner sidewall 116, a first depending sidewall 117 and a
second depending sidewall 118.

[0040] The second J-shaped body inner sidewall 116 is generally L-shaped
and consists of two generally planar members 119. The second J-shaped
body depending, sidewalls 117, 118 (FIG. 5) are generally planar. The
second J-shaped body depending sidewalk 117, 118 extend generally
perpendicular to the second J-shaped body inner sidewall planar members
119. It is noted that the outer edge of the second J-shaped body
depending sidewalls 117, 118 adjacent the vertex of the second J-shaped
body inner sidewall 116 are curved thereby giving the second J-shaped
body 94 its "J" shape. An end sidewall 113 extends between the second
J-shaped body depending sidewalls 117, 118 at the second J-shaped body
upper second end 114. As shown, the second J-shaped body end sidewall 113
may include a medial extension 115, in this configuration, the second
J-shaped body 94 defines a cavity 111 on the outer side of the second
J-shaped body 94. The second J-shaped body cavity 111 is sized to
correspond to about half of the stack of magnetically permeable members
82. That is, as shown in FIG. 5, the left half of the stack of
magnetically permeable members 82 fits within the second J-shaped body
cavity 111.

[0041] The first J-shaped body 92 and the second, J-shaped body 94 may be
coupled to form a U-shaped assembly 120 (FIG. 6). The U-shaped assembly
120 is generally symmetrical about a longitudinal-lateral plane. In this
configuration, the first J-shaped body cavity 101 and the second J-shaped
body cavity 111 form a continuous U-shaped cavity 122 that generally
corresponds to the stack of magnetically permeable members 82. Further,
the first J-shaped body first end 100 overlaps the second J-shaped body
first end 110. That is, the first J-shaped body first end 100 has a
greater cross-sectional area than the second J-shaped body first end 110.
The first J-shaped body first end 100 generally corresponds to the second
J-shaped body first end 110. Further, the first J-shaped body first end
100 may include a number of inwardly extending ledges 124 (FIG. 7). The
first J-shaped body inwardly extending ledges 124 form an abutting
surface. That is, when the second J-shaped body first end 110 is inserted
into the first J-shaped body first end 100, the second J-shaped body
first. end 110 will abut the first J-shaped body inwardly extending
ledges 124.

[0042] The first J-shaped body first end 100 overlaps the second J-shaped
body first end 110 in an axial direction, and, the first J-shaped body
first end 100 further overlaps the second J-shaped body first end 110 in
a longitudinal direction. That is, the first J-shaped body inner sidewall
106 overlaps the second J-shaped body inner sidewall 116, and, the first
J-shaped body depending sidewalls 107, 108 overlap the second J-shaped
body depending sidewalls 117, 118. More than minimally overlapping
elements resist arc penetration. That is, it is the shape of the bodies,
and the interface, that solves the problem of arcing between a multiple
piece housing assembly. In one exemplary embodiment, the first J-shaped
body first end 100 more than minimally overlaps the second J-shaped body
first end 110. Resistance to arc penetration is improved if the overlap
is more substantial. Accordingly, in another exemplary embodiment, the
first J-shaped body first end 100 effectively overlaps the second
J-shaped body first end 110. Further, in another exemplary embodiment,
the first J-shaped body first end 100 efficiently overlaps the second
J-shaped body first end 110.

[0043] Each of the first and second J-shaped body second ends 104, 114
include a tab 130, 132 (respectively, and as shown in FIGS. 7 and 8)
extending generally in an axial-longitudinal plane. Each tab 130, 132
extends above the associated end sidewall 103, 113. In an embodiment
wherein the width of the arc chute 70 loosely corresponds to the width of
the contact chamber 34, the arc chute lateral side planar member
extensions 78 are disposed inside the first and second J-shaped bodies
tabs 130, 132. That is, the arc chute first lateral side planar member 72
is disposed inside the first J-shaped body second end tab 130, and, the
arc chute second lateral side planar member 74 is disposed inside second
J-shaped body second end tab 132. In this configuration, the rigidity of
the arc chute 70 helps maintain the spacing between the first and second
J-shaped body second ends 104, 114. That is, the arc chute 70 resists the
inward collapse of the U-shaped assembly 120.

[0044] When the stationary contact assembly 60 is assembled, the slot
motor assembly 80 is disposed with the bight of the slot motor assembly
80 disposed in the gap between the stationary conductor body first end 64
and the stationary conductor body medial portion 66. The tines of the
slot motor assembly 80 extend upwardly. Thus, as the movable contact 46
moves between the first and second positions, the movable contact 46
moves between the tines of the slot motor assembly 80. An arc than forms
during separation of the contacts 14 is not likely to penetrate the slot
motor assembly housing assembly 90 because the first and second J-shaped
bodies 92, 94 more than minimally overlap at their interface.

[0045] While specific embodiments of the disclosed and claimed concept
have been described in detail, it will be appreciated by those skilled in
the art that various modifications and alternatives to those details
could be developed in light of the overall teachings of the disclosure.
Accordingly, the particular arrangements disclosed are meant to be
illustrative only and not limiting as to the scope of disclosed and
claimed concept which is to be given the full breadth of the claims
appended and any and all equivalents thereof.